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Behavior selection strategy for soccer robots

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Journal of Harbin Institute of Technology(New Series) 2001年第3期8卷 272-275页

作者： Dong M. Shin ( dept. of electrical eng., Pohang University of Science and Technology, Nam Gu, Pohang, South Korea) dept. of Elec. eng. Pohang Univ. of Sci. and Technol. KOR South Korea

The soccer robot system and the effective multi agents cooperation strategy applied to the MASKARO team composed of a set of action controllers, a set of behavior module and a behavior selector are introduced. The action is the primitive low level component of the robot control system necessary to move the robots on the playground. Each action controller determines the linear and angular velocity commands of the robots corresponding to its own purpose. The behavior is the high level component of the robot control system composed of necessary action sequences. Each behavior module determines the desired action sequences and action commands corresponding to its own objective. The behavior selector considering the information that comes from the vision system selects the behavior of each robot every sampling time. Thus, the behavior of each robot is changed dynamically. The presented strategy is successfully applied to the MASKARO team and the team is ranked in the first place in the 2000 FIRA Korea Cup K League.

关键词： behavior selection multi agents robot soccer

A NEW UEP SCHEME FOR ROBUST VIDEO TRANSMISSION IN LDPC CODED MIMO-OFDM SYSTEM

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Journal of Electronics(China) 2007年第3期24卷 396-401页

作者： Ru Congchong Zheng.Haifeng.Yin Liuguo Lu Jianhua Chen Changwen Department of Electronic eng.neering Tsinghua University Beijing 100084 China College of Information Technology Fuzhou University Fuzhou 350002 China dept. electrical ＆ Computer eng. Florida Institute of Technology Melbourne FL 32040 USA

In order to improve the video transmission performance in Multiple-Input Multiple-Output Orthogonal Frequency Division Multiplexing (MIMO-OFDM) system,a new scheme,which integrates Multiple Description Coding (MDC),Low Density Parity Check (LDPC) coding and hybrid space time coding,is proposed in this letter. In particular,a hybrid space time coding algorithm is combined with LDPC codes to perform Unequal Error Protection (UEP) of MDC encoded video streams. Comparing with the UEP transmission with only LDPC codes,the proposed scheme achieves more than 1dB gain in terms of Signal to Noise Ratio (SNR) when the Peak Signal to Noise Ratio (PSNR) of reconstructed video is above 30dB.

关键词： MIMO-OFDM系统 LDPC编码鲁棒性视频传输 UED方案

A COMPLETE COMPOSITE GTO MODEL FOR CIRCUIT SIMULATIONS

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Journal of Electronics(China) 1998年第2期15卷 130-137页

作者： Barry W. Williams dept. of Computing & electrical eng. Heriot-Watt University Edinburgh EH14 4AS U. K.

The paper presents a complete composite gate turn-off thyristor (GTO) model, which is based on the combination of the p-n-p and n-p-n transistor models. PSpice simulations and parametric sensitive analysis are performed with the complete composite model and calculated results are given, which show that it corresponds statically and dynamically with the practical device. In particular, the GTO gate dynamical characteristics in practical circuits are discussed and experimental results are included.

关键词： GTO Simulation Model

COMPOSITE SOFT SWITCHING CONFIGURATION FOR INVERTERS USING BRIDGE LEG MODULES

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Journal of Electronics(China) 2001年第1期18卷 61-69页

作者： He Xiangning Yang Yuwen (dept.of electrical eng., Zhejiang University, Hangzhou 310027)Kuang Sheng.Department of eng.neering, University of Cambridge, Cambridge, U.K.)Barry W. Williams Stephen J. Finney(dept. of Computing & electrical eng., Heriot-Watt University, Edinburgh EH14 4AS, U.K.) dept.of electrical eng. Zhejiang University Hangzhou 310027Kuang ShengDepartment of Engineering University of Cambridge Cambridge U.K.Barry W. Williams Stephen J. Finney Dept. of Computing & Electrical Eng. Heriot-Watt University Edinburgh EH14 4AS Department of eng.neering University of Cambridge Cambridge U.K. dept. of Computing & electrical eng. Heriot-Watt University Edinburgh EH14 4AS U.K.

The use of either lossless snubbers or resonant zero voltage switching (ZVS) and zero current switching (ZCS) techniques can increase efficiency and reduce electromagnetic inter ference (EMI) and noise of industrial power equipment at high switching frequencies. This paper presents an adaptive composite soft switching configuration which combines snubber functions and resonant ZCS circuits for switches in inverters using power bridge leg modules. Simulation and experimental results are included.

关键词： Inverter Snubber Soft switching IGBT modules

赛德西港用于船舶减排的陆上可再生能源供电评估

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哈尔滨工程大学学报（英文版） 2024年第2期23卷 506-524页

作者： Merna Makram Ameen M.Bassam Adel A.Tawfik Waleed Yehia Naval Architecture and Marine eng.dept. Faculty of EngineeringPort Said UniversityPort Fuad 42526Egypt

Air pollution from shipping is becoming a critical issue,particularly in dense hub port cities.One proposed solution to minimize ship-based emissions at ports is the implementation of an Onshore Power Supply(OPS)system.OPS allows ships to shut off their auxiliary eng.nes and instead connect to the port grid.While there have been numerous studies conducted on ports in Europe and the United States,little research has been done on Egyptian ports.Therefore,this paper aims to investigate the feasibility of implementing OPS at Port Said West Port in Egypt,aligning with Egypt Vision 2030’s goals for addressing climate change.The research primarily focuses on analyzing data collected from calling ships to generate socio-economic and cost-effectiveness analyses of OPS.To further enhance the environmental benefits of OPS,the paper proposes the use of solar energy as the OPS electricity source.The findings of the study revealed that by relying on the national grid,emissions can be reduced by 28%.Moreover,it is predicted that this reduction could reach 100%if electricity generation is solely based on solar energy.Additionally,the economic analysis demonstrates promising profitability,with a payback period of approximately two years.

关键词： Onshore power supply Port sustainability Shipping emissions inventory Solar energy Photovoltaic systems

Hydrodynamic Performance of Vertical Porous Structures Under Regular Waves

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China Ocean eng.neering 2013年第4期27卷 451-468页

作者： A.S.Koraim O.S.Rageh Water and Water Structure eng. dept. Faculty of Eng. Zagazig University Irrigation and Hydraulics dept. Faculty of Eng. El-Mansoura University

The hydrodynamic efficiency of the vertical porous structures is investigated under regular waves by use of physical models. The hydrodynamic efficiency of the breakwater is presented in terms of the wave transmission （kt）, reflection （kr） and energy dissipation （ka） coefficients. Different wave and structural parameters affecting the breakwater efficiency are tested. It is found that, the transmission coefficient （kt） decreases with the increase of the relative water dept. （h/L）, the wave steepness （Hi^L）, the relative breakwater widths （B/L, B/h）, the relative breakwater height （D/h）, and the breakwater porosity （n）. The reflection coefficient （kr） takes the opposite trend of kt when D/h=l.25 and it decreases with the increasing h/L, HJL and B/L when D/h〈1.0. The dissipation coefficient （kd） increases with the increasing h/L, HilL and B/L when D/h〈_l.O and it decreases when D/h=l.25. In which, it is possible to achieve values ofkt smaller than 0.3, k~ larger than 0.5, and kd larger than 0.6 when D/h=1.25, B/h=0.6, h/L〉0.22, B/L〉O. 13, and H/L 〉0.04. Empirical equations are developed for the estimation of the transmission and reflection coefficients. The results of these equations are compared with other experimental and theoretical results and a reasonable agreement is obtained.

关键词： water waves porous breakwaters wave attenuation wave transmission wave reflection wave dissipation

A Direct Compensative Robust Optimal Control (DCROC) Law for Ship Straight-line Track-keeping

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Journal of Shanghai Jiaotong university(Science) 2007年第3期12卷 364-369页

作者：李文魁田蔚风周岗陈永冰周永余 dept. of Instrument Science & eng. Shanghai Jiaotong Univ. School of electrical and Information eng. Navy Eng. Univ.

A linear quadratic optimal direct track-keeping control law was proposed based on first-order Nomoto nominal model. Furthermore, based on Lyapunov stabilized theory, considering parametric uncertainty from variations of ship speed and disturbances uncertain from wind, wave and sea current, a direct compensative robust optimal control (DCROC) law was developed. It can guarantee closed-loop system globally and uniformly converge to a remained set. High accuracy and robustness were achieved. By introducing some nonlinear blocks, closed-loop system achieves global and uniform asymptotical stableness. Numerical simulations on a Mariner Class ship are presented to validate the control law.

关键词：舵轨道补偿技术最佳控制船舶工程

A New AgMeO Contact Material

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Journal of Rare Earths 2001年第2期19卷 145-148页

作者：王景芹陆俭国温鸣王宝珠唐红梅吕玉申 dept. of electrical eng. Hebei Univ. of Technol. Tianjin 300130 China

A new silver rare earth oxide contact material, Ag/La2O3(12), was produced by powder metallurgy method. Its performances are as follows: the density is 9.71 similar to 9.96 g.cm(-3); the hardness (HB) is 760 similar to 970 MPa and the resistivity is 2.25 similar to 2.38 mu Omega . cm. The microstructure of Ag/La2O3(12) mas analyzed by SEM and EDS. Rare earth oxide La2O3 shows two shapes, which are uniformly distributed in the form of sphere and abnormality in Ag matrix. La2O3 shows fine spherical shape in the melted area of Ag after laser acting which is used to simulate electric are. The results are contributed to the less splash erosion of Ag. Compared with the main physical and mechanical properties of Ag/SnO2(12) and Ag/CdO(12), the properties of three contact materials are similar, and hence Ag/La2O3(12) may become a potential contact material to be used as the substitute of Ag/CdO(12).

关键词： rare earths contact material silver rare earth oxide powder metallurgy microstructure

Predicting the Dielectric Streng.h of c-C_4F_8 and SF_6 Gas Mixtures by Monte Carlo Method

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Journal of Shanghai Jiaotong university(Science) 2007年第1期12卷 121-124页

作者：吴变桃肖登明 dept. of electrical eng. Shanghai Jiaotong Univ.

An improved Monte Carlo method was used to simulate the motion of electrons in c-C_4F_8 and SF_6 gas mixtures for pulsed townsend discharge. The electron swarm parameters such as effective ionization coefficient, [AKα-] and drift velocity over the E/N range from 280～700 Td(1Td=10-21 V·m2) were calculated by employing a set of cross sections available in literature. From the variation cure of [AKα-] with SF_6 partial pressure p, the limiting field (E/N)_lim of gas mixture at different gas content was determined. It is found that the limiting field of c-C_4F_8 and SF_6 gas mixture is higher than that of pure SF_6 at any SF_6 mixture ratio. Simulation results show excellent agreement with experiment data available in previous literature.

关键词：绝缘体限制场气体混合电子运动